Chapter XXI: =thread-Cutting Machinery and Broaching Press.=

=Pipe Threading=, die stock for, by hand 463
Die stock for, by power 463
Pipe threading machines, general construction of 463
=Bolt Threading= hand machine 464
With revolving head 465
Power threading machine 465
With automatic stop motion 466
Construction of the head 466
Construction of the chasers 466
Bolt threading machine with back gear 467
Single rapid bolt threading machine 467
Double rapid bolt threading machine 467
Construction of the heads of the rapid machines 468
Bolt threading machinery, the Acme 468
Construction of the head of 468 to 470
Capacity of 470
=Cutting Edges= for taps, the number of 471
Examples when three and when four cutting edges are used, and
the results upon bolts that are not round 471, 472
Demonstration that four cutting edges are correct for bar iron 472
=Positions of Dies=, or chasers in the heads of bolt cutting
machine 473
=Dies=, methods of hobbing, to avoid undue friction 473
The construction of, for bolt threading machines 473
Method of avoiding friction in thread cutting 474
Hob for threading 474
Cutting speeds for threading 474
=Nut Tapping= machine 475
Automatic socket for 475
Rotary 475
Three-spindle 475
=Pipe Threading Machine= 475 to 477
=Tapping Machine= for steam pipe fittings 478
=Broaching Press= 478
Principles of broaching 478
Examples in the construction of broaches 479

FULL-PAGE PLATES.

Volume I.
_Facing_

_Frontispiece._ MODERN LOCOMOTIVE ENGINE. TITLE PAGE

PLATE I. TEMPLATE-CUTTING MACHINES FOR GEAR TEETH. 34
" II. FORMS OF SCREW THREADS. 85
" III. MEASURING AND GAUGING SCREW THREADS. 93
" IV. END-ADJUSTMENT AND LOCKING DEVICES. 120
" V. EXAMPLES IN LATHE CONSTRUCTION. 148
" VI. CHUCKING LATHES. 150
" VII. TOOL-HOLDING AND ADJUSTING APPLIANCES. 174
" VIII. WATCHMAKER'S LATHE. 188
" IX. DETAILS OF WATCHMAKER'S LATHE. 188
" X. EXAMPLES OF SCREW MACHINES. 200
" XI. ROLL-TURNING LATHE. 215
" XII. EXAMPLES IN ANGLE-PLATE CHUCKING. 252
" XIII. METHODS OF BALL-TURNING. 325
" XIV. STANDARD MEASURING MACHINES. 341
" XV. DIVIDING ENGINE AND MICROMETER. 354
" XVI. SHAPING MACHINES AND TABLE-SWIVELING DEVICES. 398
" XVII. EXAMPLES OF PLANING MACHINES. 404
" XVIII. EXAMPLES IN PLANING WORK. 422
" XIX. LIGHT DRILLING MACHINES. 428
" XX. HEAVY DRILLING MACHINES. 430
" XXI. EXAMPLES IN BORING MACHINERY. 434
" XXII. BOILER-DRILLING MACHINERY. 436
" XXIII. NUT-TAPPING MACHINERY. 475

MODERN

MACHINE SHOP PRACTICE.